For hands-on instruction on how to customize forms, see Article ID 47661: DocLink: Customizing forms training

1. Open the form in the form designer
2. Double-click on the columns text block that represents the invoice line items. This will open the Column Data Options window.
3. Click the Advanced button in the lower left hand corner of the window
4. Adjust the row spacing to the size you want
5. Click OK
6. Click Save and save the form with a new name